Electric switch



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P. RUSSELL ELECTRIC SWITCH Filed July 29, 1921 4 Sheets-Sheet 1 IWMW m M, War/a.

86.. Q9 1 L fl Y P. RU$ELL ELECTRIC SW1 TCH Filed July 29, 1921 4 Sheets-Sheet 2 ace 9 P. RUSSELL ELECTRIC swmcn Filed July 29,

4 Sheets-Sheet Data, 99 39241; 1,519,959

F. RU$$ELL ELECTRIC SWITCH Filed July 29, 1921 4 Sheets-Sheet 1 Patented Dec. 9, 1924.

UNITED STATES V 1,519,059 PATENT OFFICE.

PERCY RUSSELL, OF S'WABTHMORE, PENNSYLVANIA, ASSIGNOR T0 ELECTRO DENTAL MANUFACTURING COMPANY, OF PHILADELPHIA,- PENNSYLVANIA, A. CORPORA- TION OF PENNSYLVANIA.

ELECTRIC SWITCH.

Application filed July 29, 1921.

To all whom it may concern:

Be it known that I. PERCY RUssELL, a citizen of the United States. residing in Swarthmore, Pennsylvania, have invented Electric Switches, of which the following is a specification.

This invention relates to multi-point switches and one object thereof is to provide a switch of this tvpe in which the movable contact cannot simultaneously engage or electrically connect two fixed contacts or remain out of engagement with some one of said fixed contacts.

The invention further contemplates a switch of the above type whose construction shall be such as to prevent the movable contact short-circuiting any two of the fixed contacts, even though the distance between the latter is less than the width of that part of the movable contact which cooperates therewith, the construction being such as to insure high speed disengagement of the movable contact from each of the fixed confacts and its immediate subsequent engagement with another and adiacent fixed contact, so that the time during which the circuit is broken and the arcing between the contacts are both reduced to a minimum.

Another object of the invention is to pro- Vide a quick break, multi-point switch which shall function as above indicated regardless of the direction in which its movable contact is operated and whose construction shall be relatively simple, compact, durable, and altogether of such a nature as shall reduce to a minimum the likelihood of its getting out of order or requiring attention or repair.

I also desire to provide a multi-point switch with a novel construction and mounting for its movable contact, together with novel means for indicating the particular fixed contact engaged by the movable contact.

These objects and other advantageous ends I attain as hereinafter set forth. reference being had to the accompanying drawin s, in which,

Figs. 1 and 2 are front elevations of a switch constructed in accordance with my invention;

Figs. 3 and 4 are sections on the lines 3-3 and 4-4 respectively, Fig. 1;

Serial No. 488,384.

Fig. 10 is a perspective view of the index I plate;

Fig. 11 is a perspective view of the spring washer for the index plate;

Fig. 12 is a Iperspective view of the pointer or index mem er carried by the spindle;

Fig. 13 is a perspective View of the movable contact;

Figs. 1-1 and 15 are perspective views of one of the fixed contacts and of one of the contact-insulating plates respectively;

F 1g. 16 is a perspective view of the holding yoke for the contact-carrying plate; and

Fig. 17 is a fragmentary elevation illustrating a modified form of indicating means for my switch. 7

In the above drawings. 1 rep-resents a supporting structure of any suitable material illustrated as a plate having a cylindrical hole therethrough and formed with a boss 2 projecting from its rear face concentric with said hole.

Rotatably mounted in the hole of the supporting structure is a spindle made of the parts shown more particularly in Figs. 3 and 9 and including a sleeve 3 rotatably mounted in said supporting structure. This sleeve has integral with or connected to it a flange 4. countersunk in the outer face of said structure and is closed at its flanged "end, having also a shoulder 8 a polygonal portion 5 and a threaded stem 6. Fitted to this polygonal portion is an index member 7 having a pointer 8 designed to cooperate with a series of point indicating numbers on the adjacent face of an index plate 9, rotatably mounted on the shoulder 3* adjacent the flange 4:.

A concave spring washer 10 is mounted between the index plate 9 and the member 7 so as to create a certain amount of friction between these elements andat the same time prevent or take up lost motion. The index plate 7 is confined on the polygonal portion 5 of the sleeve by a nut 11 on the stem 6, which is also threaded into a metallic bushing 12 fixed in any suitable manner axially within a handle 13.

Within the hollow of the rotatable sleeve 3 is mounted afluted or longitudinally roughened stem 14 which is integral with a flange 15, a threaded hub 1.6, a ournal 17 and a head 18. Said stem 14a is electricaily insulated from the sleeve 3 by a second sleeve 19 into which it is driven so as to be 1110apable of movement and which in turn is forced into said sleeve 3 so that all of said parts are immovably connected; there being also an insulating washer 20 mounted on the stem 1 between the flange 15 thereof and the adjacent end of the sleeve 3. As consequence of this construction, the rear end of the spindle constituted by the stem 14:, hub 16, etc., is insulated from the opposite end thereof formed by the sleeve 3, the stem 6, etc.

The journal 17 of the stem rotatably engages or has a bearing wlthin a plate or block 21 of insulating material formed with a circularly curved edge portion and a projecting arm 22 which is gripped between and held immovable by the arms of a yoke member 24 (Fig. 16) held by a. screw 25 to and projecting rearwardly from the rear face of the supporting structure 1. The head 18 of the spindle is connected to the ournal portion 17 thereof by a neck designed to receive and fit between the branches of a forked spring 26 held by a screw 27 to the arm 22 of the insulating plate 21. Said spring is so formed as to press the plate 21 against a collar 28 threaded, on the hub portion 16 of the spindle, where it is retained by a set screw 29 (Fig. 3). The face of this collar, rotatably engages and slides upon the adjacent face of the insulating plate 21 so as to assist in maintaining the spindle perpendicular thereto and prevent it from wobbling.

The movable contact member of the switch consists of a body of spring sheet material 30 (Fig. 13) in the form of a ring having a projecting spring arm terminating in or constituting a flat contact finger 31. Said ring in the present instance is connectedto the flange 15 by a pair of struck up lugs 32 which enter oppositely placed recesses therein.

The fixed contact elements of the switch are each constructed as shown in Fig. 14 and are all mounted on the edge of the insulating support 21, which for this purpose is curved concentrically with the spindle on which the movable contact 30 is mounted and which as above noted, carries the operating handle 13.

The fixed contacts are preferably made of stamped or struck up Sheet material, although obviously they may be cast or otherwise made without departing from my invention. Each contact consists of a body portion 33 and a laterally projecting or overhung head portion made in two parts 341 and 35, spaced apart and lying substantially in parallel planes to permit of the assage between them of the finger 31 of the movable contact. These overhung parts constituting the heads of the fixed contacts all intersect and are inclined at a more or less acute angle to the general plane of movement of the movable contact 30 and their bodies 33 are so mounted on the circularly curved edge of the supporting plate 21 that each of the parts 34. of its head extends over or overlaps the part 35 of the contact to which it is adjacent, although it is spaced away from the latter a sufficient distance permit of the introduction of the head portion 411 of an insulating plate or sheet, each of which has a body similar to the body of the fixed contact with which it is associated. These insulating i'ncmbers have the form shown in Fig. 15 and each of them with its associatcd fixed contact is held to the edge of the supporting plate 21 by a screw 42, the lower end of each contact being bent upon itself and having a terminal screw threaded in it (Fig. 3). The fixed contacts are thus arranged with their bodies fixed to the circularly curved edge of the plate 21 and with their laterally projecting heads overlapping, so that the finger 31 of the movable contact will normally project in a position slightly below but parallel with the inclined top surface of the portion 34 of each of the fixed contacts but at the same time at a. level slightly above the under surface of tho portions 35 of said contacts.

If, as shown in Fig. 5, the spring finger 31 be resting upon the upper surface of the part 34 of one of the fixed contacts and the handle thereafter be turned in a clockwise direction, said finger will ride upon the contact until it drops off of the high edge thereof onto the top surface of the part 34 of the adjacent fixed contact. Since the finger is flexed above its normal position at the time it drops from one contact to the other, its passage between said contacts is practically instantaneous, so that the breakage of the circuit in which it is included is so short as to be practically negligible. At the same time, there is no possibility of the movable contact short circuiting any two of the fixed contacts. Moreover the top surfaces of the fixed contacts and the under surface of the finger 31 have the same inclination so that good electrical contact of the parts is assured without possibility of heating or burning of the contacts.

Whennft-er the movable contact has been turned as far to the right as is permitted by the end wall of the recess 51, impinging against the head of the screw 50, threaded into the supporting plate 1; and its direction of movement is reversed, its top surface strikes the inclined under surface of the part 35 of the end contact, which bends it below its normal plane of movement as it is turned, so that when it finally disengages this part, it snaps into engagement with the under side of the part 35 of the next fixed contact to the left. Owing to the overlapped arrangement ofthe fixed contacts, the further movement in the counter-clockwise direction of the movable contact causes its finger to snap successively from engagement with the under side of each of the parts 35 to the under side of a similar part adjacent to it on the left, and as previously described, owing to the offset construction of the parts of the head of the fixed contacts, there is a sudden drop in each instance of said finger from one fixed contact to the next, it being noted that when moving in a co.unter-clockwise direction the movable contact engages only the bottom faces of the parts 35, while when moving in a clockwise direction it engages only the to faces of the parts 34. In any case the quic break action not only prevents burning but minimizes the duration of break of the circuit and insures that there shall be no short-circuiting of the fixed contacts by the movable contact.

'moves into engagement with the under side of the portion 35 of the same fixed contact, from which, as its counter-clockwise movement is continued, it drops onto the similar portion of the next fixed contact to the left. If now its direction of movement be reversed so that it is turned in a clockwise direction,

it slides from the under side of the part 35 of the fixed cont-act, through the opening between it and the adjacent edge of the part 34 of the same contact, riding up on the latter and finally dropping OR of the right hand edge of the same onto the part 34 of the next adjacent fixed contact.

In order to limit the angular movement of the handle 13 and therefore of the movable contact, I mount a screw 50 on the supporting structure or plate 1 so that its headprojects from the front thereof into a segmental recess 51 formed in the under side of the index member 7. This is so fixed on the spindle that when the finger of the movable contact member engages the endmost of the fixed contacts on either side, one end wall of the recess 51 comes into engagement with the head of the screw 50, thus preventing furthermovement of the handle and its associated parts.

lVith the above described construction it will be obvious that the pointer 8 of the index should indicate on the index plate 9 a number designating the particular time the direction ofmovement o fixed contact which is engaged at any time by the movable contact, but since when the direction of movement of the latter is reversed it coacts with the parts 34 in one case and with the parts 35 in the other, I make said index plate with a slot 52 (Figs. 1, 2, and 10) for the reception of the head of the screw 50 and make such slot larger than said head by an amount equal to the angular-distance between the centers of the two parts 34 and 35 constituting the head of any one fixed contact. Go uently each the spindle 1s reversed, the index plate 9,.owing to the frictional action of the s rin washer 10, turns with the spindle and index until one end of its slot 52 strikes the head of the screw 50, after which its'further movement 18 prevented. The index thereafter moves relatively to-the index plate so as to correctly indicate the particular fixed contacts engaged by the movable contact; it being obviously immaterial whether the index or the plate be immovably fixed to the spindle since it is essential only. that one of these parts he fixed to the spindle and the other have a limited In vement and connection with the supporting structure.

In order to take u any lost motion between the s indle an its supportin structure, I pre erably mount between tie part 30 and an insulating washer 90 a spring plate 55 which serves-to draw inwardly the whole spindle assembly, maintaining the flange 4 against the bottom of the recess in which it is mounted. 'While I preferably employ the insulating plates 41 between the under side of the parts 34 of the fixed contacts and the ad acent top faces of the parts 35 of the contact to the right thereof, these may in some cases be omitted, but I prefer to employ them so as to prevent danger of one contact being pressed into engagement with another by the action of the movable contact 31.

From the above description it will be noted that while the finger 31 of the movable contact is much wider than the distance between adjacent fixedcontacts, there is none the less no possibility of its even momentarily short-circuiting any two of the loo latter. At the same time it always rests in engagement with one of the fixed contacts since the length oi. the recess in the By the term plane of movement of the movable contact it is to be understood that reference is had to the plane at rightangles to the ones of the spindle 17 in which said contact would move if undeflected by the fixed contacts.

Without departing from my invention other means than the relatively movable index plate and index may be provided for correctly indicating the particular one of the fixed contacts engaged at any time by the movable contact and as illustrative of such a modification of my device I may provide the arrangement shown in Fig. 17 which includes an indicating scale applied directly to or mounted adjacent the plate carrying the fixed contacts so as to cooperate with the movable contact arm. Such a scale includes two parts 71 and 72 arranged in the form of concentric arcuate areas having the same angular length as that of the line of the fixed contacts and divided into spaces, each having an angular width equal to that of one of the parts 34 or 35 of a fixed contact. The spaces in the outer portion 72 of the scale are numbered 1 to 8 and that at the left hand end of the series has suitably positioned within it an arrow pointing in a clockwise direction to indicate that the numbers on the adjacent. spaces are correct or are to be employed when the movable contact is being moved in a clockwise direction. The spaces in the part 71 of the scale are likewise numbered from 1 to S, but owing to the above described construction and ar 'angement of the fixed con tacts, these numbers are displaced to the left relatively to the numbers of the part 72 of the scale for an amount equal to one space or division. A second arrow is applied to this part 71 of the scale to indicate that its figures are to be read or employed to indicate the contact engaged by the movable contact member as this is being moved in a counter-cloclnvise direction.

I claim:

.l. The combination in an electric switch of a movable contact; and a series of fixed contacts having portions lying in substantially parallel planes inclined to the plane of movement of the movable contact and including means whereby said movable contact automatically caused to move into engagcn'ient with opposite faces of the fixed contacts when its direction of movement is reversed, the adjacent portions of adjacent contacts being in stepped relation and posiis reversed, said fixed contacts being posi tioned to cause said movable contact to instantaneously snap from one fixed contact to another when it is moved in either direction.

3. The combination in an electric switch of a series of fixed contacts spaced apart, said fixed contacts having 0 posite faces: and a movable contact wider t an the spaces between the fixed contacts and including means whereby said movable contact is automatically caused to move into engagement with opposite faces of the fixed contacts when the direction of movement thereof is reversed, said fixed contacts being positioned to cause said movable contact to instantaneously snap from one fixed contact to another when it is moved in either direction.

4. The combination in an electric switch of a reversible rotary contact member; with a series of overlapping fixed contacts adapted to be engaged by said rotary member and having spaces between them, said fixed contacts being formed to prevent the rotary member simultaneously engaging any two of them.

5. The combination in an electric switch of a series of independent overlapping fixed contacts; and a movable contact formed to engage different sides of said fixed contacts when its direction of movement is reversed.

6. The combination in an electric switch of a series of overlapping fixed contacts; a movable contact formed to engage with opposite faces of said fixed contacts when its direction of movement is reversed, the overlapping portions of said fixed contacts being spaced apart; with insulating material between said overlapping portions.

7. The combination in an electric switch of a series of fixed contacts each including two portions lying in parallel planes; and a movable contact formed to engage different sides of said fixed contacts when it moves in opposite directions.

8. The combination in an electric switch of a series of fixed contacts each including two portions lying in parallel planes; and a movable contact formed to engage different sides of said fixed contacts when it moves in opposite directions and to pass between the parts of each fixed contact when its movement is reversed.

9. The combination in an electric switch of a movable contact; with a series of fixed contacts coacting therewith, each of said fixed contacts having two parallel overhung portions inclined at an angle to the plane of movement of the movable contact and having the adjacent edges of said parts spaced to permit passage between them of said movable contact, said fixed contacts overlapping each other and each presenting two faces for cooperation with the movable contact.

10. The combination in an electric switch of a supportii'ig structure; a movable contact mounted thereon; with a series of fixed contacts adapted to be engaged by said movable contact, said fixed contacts having overlapping head portions and body port'ons connected to the supporting structure. each of said head portions consisting of two substantially fiat parts lying sul'istantially parallel with each other and inclined to the plane of movement of the movable contact, the adjacent edges of said parts being spaced to permit of the passage between them of the movable contact.

11. The combination in an electric switch of a supporting structure; a movable contact mounted thereon; with a series of fixed contacts adapted to be engaged by said movsubstantially parallel with the inclined portions of the fixed contacts.

12. The combination in an electric switch of a supporting structure; a spindle having a handle rotatably mounted on said structure; a resilient contact finger carried by the spindleywith a series of independent overlapping fixed contacts positioned on the supporting structure and each presenting two opposite faces for engagement with the movable contact.

13. The combination in an electric switch of a supporting structure; a spindle having a handle rotatably mounted on said structure; a resilient contact finger carried by the spindle; with a series of overlapping fixed contacts positioned on the supporting structure and each presenting two opposite faces for engagement with the movable contact, the latter and the overhung portions of the fixed contacts being inclined at an acute angle to the plane of movement of the movable contact.

14.. The combination in an electric switch of a resilient movable contact; a series of fixed contacts each having two portions inclined to the plane of movement of the movable contact and each having opposite faces for coaction with the latter, each of the fixed contacts having two contact portions of which one is on one side and the other is on the opposite side of the plane of movement of the movable contact.

15. The combination in an electric switch of a supporting structure; a spindle rotatably mounted thereon; a movable contact "for the spindle; a series of two-part fixed contacts mounted on the supporting structure in positions to coact with the movable contact; an index fixed to the spindle; and an index plate for indicating the fixed contact engaged by the movable contact.

16. The combination in an electric switch of a series of fixed contacts, each having two portions inclined at an acute angle with the line of such series; and a reversible contact having'a finger provided with a contact face substantially parallel with the inclined portions of the fixed contacts.

17. The combination in an electric switch of a series of fixed contacts each having a two-part head; with a movable contact engaging one part of each of the heads when it is moved in one direction and engaging. with the second parts of said heads when it is moved in the opposite direction.

18. The combination in an electric switch of a series of. fixed contacts each having .a two-part head and a movable contact operative in engagement with one part of said heads on one side of the series of contacts when it moved in one direction and operative in engagement with the other parts of the heads on the opposite side of the series of contacts when it is moved in an opposite direction.

19. The combination in an electric switch of a series of fixed contacts each having a twopart head; axmovable contact engaging one part of each of the heads when it is moved in one direction and engaging the second parts of said heads when it is moved in the opposite direction; with indicating means including an index having a lost motion connection with the movable contact for showing which one of the fixed contacts is engaged thereby.

20. The combination in an electric switch of a series of fixed contacts each having a two-part head; a movable contact cooperating with one part of each of the heads when it is moved in one direction and with the second parts of said heads when it is moved in the opposite direction; indicating means including an index member. having alost motion connection with the movable contact; and means for causing said index member and movable contact to move together through a predetermined angle when the movable contact is reversed.

21. The combination in an electric switch of a series of fixed contacts each having a two-part head; a movable contact cooperating with one part-of each of the heads when it is moved in one direction and with the second parts of said heads when it is moved in the opposite direction; indicating means including an index member having a limited motion connection with the supporting structure; and means for causing.

said index member and movable contact to move together, when the movable contact is reversed, through the angle subtended by the distance between the centers of the two head portions of a fixed contact.

22. The combination in an electric switch of a movable contact and a series of fixed contacts each having two substantially fiat contact plates both inclined to the line of said contacts and spaced apart to permit passage between them of the movable contact, the plates of each fixed contact respectively over and underlapping plates of adjacent fixed contacts.

23. The combination in an electric switch of a supporting structure; a spindle journaled therein; a reversible movable contact carried by the spindle; an insulating plate also carried by the supporting structure and providing a bearing for the spindle; a series of contacts mounted on said plate and having laterally extended contact portions positioned to cooperate with the movable contact when it is turned in either of the directions; and a handle for the spindle.

24. The combination of a supporting structure having a bearing a two-part spindle having a tubular portion extending into said bearing; and an inner portion projecting into said tubular portion; means for electrically insulating one part of said spindle from the other; a series of fixed con tacts and a movable contact connected to one part of the spindle; with a handle for the other part-of the spindle.

25. The combination in an electric switch of a series of fixed contacts each having two contact parts; a movable contact; a spindle for actuating the movable contact; an index fixed to the spindle; an index plate mounted to cooperate with the index; with means for causing limited movement to be imparted from the spindle to the index plate when the direction of movement of the spindle is reversed.

26. The combination in an electric switch of a supporting structure having a projection; a spindle rotatably supported by said structure; a handle for said spindle; an index plate frictionally engaging the spin dle and. having a slot for the reception of the projection; an index cooperating with said plate and fixed to the spindle; a movable contact carried by the spindle; and a series of fixed contacts mounted to cooperate with the movable contact.

27. The combination in an electric switch of a series of contacts arranged in stepped relation and each including two separated parts; with a relatively movable contact free to pass between the parts of any of said series of contacts, from one side to the other of the line of contacts, when its di reotion of movement is reversed.

28. The combination inan electric switch of a series of contacts arranged in stepped relation; with a relatively movable contact free to pass between any two of said series of contacts when its direction of movement is reversed, and positioned to snap instantaneously from engagement with one contact into engagement with another as it is moved in either direction.

29. In an electric switch, the combination of a movable contact and a series of fixed contact pieces formed to present two series of contact faces; one series of faces adapted to be successively engaged one at a time by the movable contact when moved in one direction and the other series adapted to similar coaction with the movable contact when the latter is moved in the opposite direction; with means for automatically shifting the movable contact from engagement with any contact face belonging to one series into engagement with a contact face belonging to the other series when its direction of movement is reversed.

30. The combination in an electric switch of a series of relatively fixed contacts and a relatively movable contact adapted to move in two directions and to make electrical connection with said fixed contacts one at a time when moved in either direction; said fixed contacts being positioned to cause said movable contact to instantaneously pass from one fixed contact to another when it is moved in either direction and formed to ma tain. an uninterrupted electrical connection tact except at the moment of each instantaneous passage from one fixed contact to another.

31. The combination in an electric switch of a series of fixed contacts each having a portion inclined at an acute angle to the lineof such series; with a reversible movable contact having a fiat finger twisted to lie substantially fparallel with the inclined portions of the xed contacts.

PERUY RUSSELL.

an movable con- 

